vm2 before 3.12.2 contains an authorization bypass in the NodeVM external-module resolver. (CVE-2026-100721)
vm2 versions prior to 3.12.2 have an authorization bypass vulnerability in the NodeVM external-module resolver. This flaw allows untrusted guest code to load and execute code from non-allowlisted sibling modules by exploiting how resolved module paths are matched. The vulnerability leads to sandbox escape and arbitrary code execution in the host context.
AI Analysis
Technical Summary
The vulnerability in vm2 before version 3.12.2 arises from improper authorization checks in the NodeVM external-module resolver when a custom resolver is configured with `require.external` and `context: 'host'`. The resolver records allowed module directories using a regular expression that does not enforce path boundaries, allowing untrusted code to require sibling modules whose paths share a prefix with allowlisted modules. This bypasses the intended allowlist, causing the sibling module's top-level code to execute in the host process before sandboxing, resulting in arbitrary code execution and sandbox escape.
Potential Impact
Successful exploitation allows untrusted guest code to escape the vm2 sandbox and execute arbitrary code in the host environment with the privileges of the host process. This compromises the isolation guarantees of vm2, potentially leading to full host compromise.
Mitigation Recommendations
A fix is available in vm2 version 3.12.2. Users should upgrade to version 3.12.2 or later to remediate this vulnerability. No other mitigations are indicated.
vm2 before 3.12.2 contains an authorization bypass in the NodeVM external-module resolver. (CVE-2026-100721)
Description
vm2 versions prior to 3.12.2 have an authorization bypass vulnerability in the NodeVM external-module resolver. This flaw allows untrusted guest code to load and execute code from non-allowlisted sibling modules by exploiting how resolved module paths are matched. The vulnerability leads to sandbox escape and arbitrary code execution in the host context.
CVSS v3.1
Score 9.0critical
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in vm2 before version 3.12.2 arises from improper authorization checks in the NodeVM external-module resolver when a custom resolver is configured with `require.external` and `context: 'host'`. The resolver records allowed module directories using a regular expression that does not enforce path boundaries, allowing untrusted code to require sibling modules whose paths share a prefix with allowlisted modules. This bypasses the intended allowlist, causing the sibling module's top-level code to execute in the host process before sandboxing, resulting in arbitrary code execution and sandbox escape.
Potential Impact
Successful exploitation allows untrusted guest code to escape the vm2 sandbox and execute arbitrary code in the host environment with the privileges of the host process. This compromises the isolation guarantees of vm2, potentially leading to full host compromise.
Mitigation Recommendations
A fix is available in vm2 version 3.12.2. Users should upgrade to version 3.12.2 or later to remediate this vulnerability. No other mitigations are indicated.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-c9wr-qm7p-p6vc
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-100721"]
- Database Specific Severity
- CRITICAL
- Cvss Version
- 3.1
Threat ID: 6ab89bc2f7a7c54106941ed4
Added to database: 09/27/2026, 04:29:54 UTC
Last enriched: 09/27/2026, 04:36:49 UTC
Last updated: 09/27/2026, 06:47:45 UTC
Views: 21
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